Michael Jackson probably caused his own death by injecting himself with Propofol, an expert anaesthesiologist claimed in court today (28.10.11).

Defence witness Paul White took to the stand in the involuntary manslaughter trial of Dr. Conrad Murray and directly challenged the testimony of the prosecution's main medical witness Dr. Steven Shafer.

Shafer had told the jury in his opinion the only plausible explanation for Jackson's death on June 29, 2009, was that Murray had administered the anaesthetic Propofol and left it running into his system, even after the singer had stopped breathing - the theory the prosecution has always maintained.

Defence lawyer Michael Flanagan asked White: "You think it was self-injection of Propofol ... between 11.30 and 12 o'clock? (that caused Jackson's death)"

To which White - who performed clinical studies of Propofol for years before it was approved for use by the Food and Drug Administration in 1989 - replied: "In my opinion, yes."

Later on in his testimony, White also corroborated a defence theory that the 'Thriller' singer swallowed several pills of the sedative lorazepam and that drug combined with the Propofol created a "perfect storm" of substances that killed him.

White said: "The fact that there is even a tiny amount of free lorazepam is consistent with the theory that he took lorazepam orally."

Flanagan quizzed White on whether the drugs Murray admitted to giving Jackson in his police interview - small injections of two sedatives and a half dose of Propofol - could have caused the singer's passing, asking: "Would this present a Dangerous situation here?"

White said: "Not at all."

White also claimed the level of Propofol found in Jackson's urine at his autopsy was consistent with his opinion that the pop legend gave himself the drug.

He also claimed he had been presented with no evidence that supported the prosecution's claims Murray had been administering Jackson with Propofol via an IV drip at the star's rented Los Angeles mansion.

During his testimony for the prosecution, Shafer argued the blood levels of Propofol in Jackson's system did not support the defence's self-injection theory.

Superior Court Judge Michael Pastor has recessed the case - which has been running for five weeks - until Monday (31.10.11) when the cross-examination of White, the defence's final witness, will continue.

Murray - who denies involuntary manslaughter - faces up to four years in prison if he is found guilty.